Neotrichia xereuini sp nov.

Figures: 6A–6D

Diagnosis. This species does not fit well into any of the Species Groups of Marshall (1979) as defined by Keth et al. (2015). The male of Neotrichia xereuini sp. nov. is similar to that of Neotrichia orlandoi Santos & Nessimian 2009 in that the posteroventral margin of segment IX is produced into a long lobe in ventral view (Fig. 6B) and the subgenital plate is bifid (Fig. 6A, sg). The new species differs from N. orlandoi by lacking a sclerotized process on the posterodorsal margin of segment IX, by having subapical dilations of the inferior appendages (Fig. 6B), and by the phallus ending in a pair of sharply bent apical processes (Fig. 6D).

Description. Male (in alcohol): Dark brown, with length of each forewing 1.3 mm (holotype). Postoccipital setal warts pronounced, large, ovoid. Antennae each with 18 articles; scape normal, cylindrical, slightly longer than pedicel; flagellomeres each as long as pedicel, cylindrical. Maxillary palp formula I-II-IV-III-V (shortest to longest), first two articles shorter than wide. Mesoscutellum with anterior margin convex; metascutellum convexly subtriangular.

Male genitalia. Segment IX with anterolateral margins rounded in lateral view (Fig. 6A), segment IX subquad-rate with subquadrate anterodorsal incision in dorsal view (Fig. 6C) and with broadly rounded and shallower anteroventral incision in ventral view (Fig. 6B); posteroventral margin produced into mesal, long and apically rounded lobe (Fig. 6B, pvm); in lateral view posterolateral margins sinuous, with paired slender membranous processes much shorter than segment X, each bearing one apical seta (Fig. 6A, mp). Bracteoles absent. Segment X fused with dorsum of segment IX; quadrate with membranous apex truncate in lateral and dorsal views (Figs. 6A, 6C). Subgenital plate in lateral view bifid distally, dorsal branch produced posterad and tapering to acute apex flanked by pair of elongate setae; ventral branch produced ventrad, longer, tapering to acute apex (Fig. 6A, sg); in ventral view wide basally, dorsal branch narrowing distally to acute medial process flanked by pair of elongate setae, ventral branch drop-like (Fig. 6B, sg). Inferior appendages long and bifid; in lateral view, each with lateral process slender and tapered to acute apex; mesal process slender, produced ventrally and nearly hidden by lateral process, slightly tapered to apex having single apical seta (Fig. 6A, ia); in ventral view, lateral process dilated subapically, tapering to acute apex; mesal process about one-half length of dorsal process, slender, narrowing distally and bearing apical seta (Fig. 6B, ia). Phallus elongate with wide tubular base narrowing to median constriction; paramere encircling shaft and extending posterad half length of phallus apical portion and hooked anterad apically (Fig. 6D, pr); apical portion slender, ending in pair of heavily sclerotized and sharply bent processes at apex, lower process curving upward in dorsal view (Fig. 6D); ejaculatory duct protruding subapically (Fig. 6D, ed).

Female, larva, pupa, and egg. Unknown.

Holotype male. BRAZIL: Roraima: Iracema municipality, Vicinal Campos Novos (Fazenda Rancho Fundo), small order stream, 2°21’26.22”N, 61°23’38.98”W, 209 m a.s.l., 16 Mar. 2018, Pennsylvania light trap, J.L. Gama Neto, leg. (alcohol; MPEG).

Distribution: Brazil (Roraima, type locality only).

Etymology. The specific name “ xereuini ” is a noun used in apposition, referring to the Xereuini River, a western tributary of the Branco River.